Dielectric Properties of P(VDF-TrFE-CTFE) Composites Filled with Surface-Coated TiO₂ Nanowires by SnO₂ Nanoparticles

Nanocomposites containing inorganic fillers embedded in polymer matrices have exhibited great potential applications in capacitors. Therefore, an effective method to improve the dielectric properties of polymer is to design novel fillers with a special microstructure. In this work, a combination of hydrothermal method and precipitation method was used to synthesize in situ SnO₂ nanoparticles on the surface of one-dimensional TiO₂ nanowires (TiO₂ NWs), and the TiO₂NWs@SnO₂ fillers well-dispersed into the poly (vinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene) [P(VDF-TrFE-CTFE)] polymer. Hybrid structure TiO₂NWs @SnO₂ introduce extra interfaces, which enhance the interfacial polarization and the dielectric constant. Typically, at 10 vol.% low filling volume fraction, the composite with TiO₂NWs @SnO₂ shows a dielectric constant of 133.4 at 100 Hz, which is almost four times that of polymer. Besides, the TiO₂ NWs prevents the direct contact of SnO₂ with each other in the polymer matrix, so the composites still maintain good insulation performance. All the improved performance indicates these composites can be widely useful in electronic devices.